The diabetic patient should learn to recognize symptoms of low blood sugar (such as confusion, sweats, and palpitations) and high blood sugar (such as, polyuria and polydipsia). When either condition results in hospitalization, vital signs, weight, fluid intake, urine output, and caloric intake are accurately documented. Serum glucose and urine ketone levels are evaluated. Chronic management of DM is also based on periodic measurement of glycosylated hemoglobin levels (HbA1c). Elevated levels of HbA1c suggest poor long-term glucose control. The effects of diabetes on other body systems (such as cerebrovascular, coronary artery, and peripheral vascular) should be regularly assessed. Patients should be evaluated regularly for retinal disease and visual impairment and peripheral and autonomic nervous system abnormalities, e.g., loss of sensation in the feet. The patient is observed for signs and symptoms of diabetic neuropathy, e.g., numbness or pain in the hands and feet, decreased vibratory sense, footdrop, and neurogenic bladder. The urine is checked for microalbumin or overt protein losses, an early indication of nephropathy. The combination of peripheral neuropathy and peripheral arterial disease results in changes in the skin and microvasculature that lead to ulcer formation on the feet and lower legs with poor healing. Approx. 45,000 lower-extremity diabetic amputations are performed in the U.S. each year. Many amputees have a second amputation within five years. Most of these amputations are preventable with regular foot care and examinations. Diabetic patients and their providers should look for changes in sensation to touch and vibration, the integrity of pulses, capillary refill, and the skin. All injuries, cuts, and blisters should be treated promptly. The patient should avoid constricting hose, slippers, shoes, and bed linens or walking barefoot. The patient with ulcerated or insensitive feet is referred to a podiatrist for continuing foot care and is warned that decreased sensation can mask injuries.
Diabetes is among the leading causes of kidney failure, but its frequency varies between populations and is also related to the severity and duration of the disease. Several measures to slow down the progress of renal damage have been identified. They include control of high blood glucose, control of high blood pressure, intervention with medication in the early stage of kidney damage, and restriction of dietary protein. Screening and early detection of diabetic kidney disease are an important means of prevention.

Most pediatric patients with diabetes have type 1 diabetes mellitus (T1DM) and a lifetime dependence on exogenous insulin. Diabetes mellitus (DM) is a chronic metabolic disorder caused by an absolute or relative deficiency of insulin, an anabolic hormone. Insulin is produced by the beta cells of the islets of Langerhans located in the pancreas, and the absence, destruction, or other loss of these cells results in type 1 diabetes (insulin-dependent diabetes mellitus [IDDM]). A possible mechanism for the development of type 1 diabetes is shown in the image below. (See Etiology.)

Insulin Therapy. Exogenous insulin is given to patients with diabetes mellitus as a supplement to the insufficient amount of endogenous insulin that they produce. In some cases, this must make up for an absolute lack of insulin from the pancreas. Exogenous insulin is available in various types. It must be given by injection, usually subcutaneously, and because it is a potent drug, the dosage must be measured meticulously. Commonly, regular insulin, which is a fast-acting insulin with a short span of action, is mixed with one of the longer-acting insulins and both types are administered in one injection.

Low blood sugar (hypoglycemia), is common in people with type 1 and type 2 DM. Most cases are mild and are not considered medical emergencies. Effects can range from feelings of unease, sweating, trembling, and increased appetite in mild cases to more serious effects such as confusion, changes in behavior such as aggressiveness, seizures, unconsciousness, and (rarely) permanent brain damage or death in severe cases.[24][25] Moderately low blood sugar may easily be mistaken for drunkenness;[26] rapid breathing and sweating, cold, pale skin are characteristic of low blood sugar but not definitive.[27] Mild to moderate cases are self-treated by eating or drinking something high in sugar. Severe cases can lead to unconsciousness and must be treated with intravenous glucose or injections with glucagon.[28]
Before blood glucose levels rise, the body of a person destined for type 2 becomes resistant to insulin, much as bacteria can become resistant to antibiotics. Insulin is the signal for the muscles, fat, and liver to absorb glucose from the blood. As the body becomes resistant to insulin, the beta cells in the pancreas must pump out more of the hormone to compensate. People with beta cells that can't keep up with insulin resistance develop the high blood glucose of type 2 diabetes.
Clear evidence suggests a genetic component in type 1 diabetes mellitus. Monozygotic twins have a 60% lifetime concordance for developing type 1 diabetes mellitus, although only 30% do so within 10 years after the first twin is diagnosed. In contrast, dizygotic twins have only an 8% risk of concordance, which is similar to the risk among other siblings.
While poor vision is hardly uncommon—more than 60 percent of the American population wears glasses or contacts, after all—sudden changes in your vision, especially blurriness, need to be addressed by your doctor. Blurry vision is often a symptom of diabetes, as high blood sugar levels can cause swelling in the lenses of your eye, distorting your sight in the process. Fortunately, for many people, the effect is temporary and goes away when their blood sugar is being managed.
It’s not uncommon for patients to suddenly feel unsteady and immediately need to reach for carbs, says Marjorie Cypress, a nurse practitioner at an endocrinology clinic in Albuquerque, New Mexico, and 2014 president of health care and education for the American Diabetes Association. “When you have high blood sugar, your body has a problem regulating its glucose,” she explains. “If you’ve eaten something high in carbohydrates, your body shoots out a little too much insulin, and your glucose drops quickly. This makes you feel shaky, and you tend to crave carbs or sugar. This can lead to a vicious cycle.” These are the best foods for someone on a diabetic diet.
While discovering you have diabetes can be a terrifying prospect, the sooner you’re treated, the more manageable your condition will be. In fact, a review of research published in the American Diabetes Association journal Diabetes Care reveals that early treatment with insulin can help patients with type 2 diabetes manage their blood sugar better and gain less weight than those who start treatment later.
What does the research say about proactive type 2 diabetes management? Research shows that proactive management can pay off in fewer complications down the road. In the landmark UKPDS study, 5,102 patients newly diagnosed with type 2 diabetes were followed for an average of 10 years to determine whether intensive use of blood glucose-lowering drugs would result in health benefits. Tighter average glucose control (an A1c of 7.0% vs. an A1c of 7.9%) reduced the rate of complications in the eyes, kidneys, and nervous system, by 25%. For every percentage point decrease in A1c (e.g., from 9% to 8%), there was a 25% reduction in diabetes-related deaths, and an 18% reduction in combined fatal and nonfatal heart attacks.
It is a considerable challenge to obtain the goals of the intensively treated patients in the DCCT with the vast majority of people with diabetes given the more limited health care resources typically available in routine practice. If diabetes control can be improved without significant damage to quality of life, the economic, health, and quality of life savings associated with a reduction in complications in later life will be vast. Although some people who have had poorly controlled diabetes over many years do not develop complications, complications commonly arise after 15–20 years of diabetes and individuals in their 40s or even 30s may develop several complications in rapid succession. However, up until the early 1980s, patients had no way of monitoring their own blood glucose levels at home. Urine glucose monitoring only told them when their blood glucose had exceeded the renal threshold of approximately 10 mmol/L (i.e., was far too high), without being able to discriminate between the too high levels of 7–10 mmol/L or the hypoglycemic levels below 4 mmol/L. Clinics relied on random blood glucose testing and there were no measures of average blood glucose over a longer period. Since the 1980s there have been measures of glycosylated hemoglobin (GHb, HbA1, or HbA1c) which indicate average blood glucose over a six to eight week period and measures of glycosylated protein, fructosamine, which indicates average blood glucose over a two-week period. Blood-glucose meters for patients were first introduced in the early 1980s and the accuracy and convenience of the meters and the reagent strips they use has improved dramatically since early models. By the late 1990s blood-glucose monitoring is part of the daily routine for most people using insulin in developed countries. Blood-glucose monitoring is less often prescribed for tablet- and diet-alone-treated patients, financial reasons probably being allowed to outweigh the educational value of accurate feedback in improving control long term. The reduced risk of hypoglycemia and diabetic ketoacidosis in NIDDM patients not using insulin means that acute crises rarely arise in these patients though their risk of long-term complications is at least as great as in IDDM and might be expected to be reduced if feedback from blood-glucose monitoring were provided.
Prediabetes is a condition in which blood glucose levels are higher than normal, but a person does not yet have diabetes. Prediabetes and high blood glucose levels are a risk factor for developing diabetes, heart disease, and other health problems. Other warning signs prediabetes may include increased urination, feeling you need to urinate more often, and/or increased thirst.
Diabetes mellitus is classified into four broad categories: type 1, type 2, gestational diabetes, and "other specific types".[11] The "other specific types" are a collection of a few dozen individual causes.[11] Diabetes is a more variable disease than once thought and people may have combinations of forms.[37] The term "diabetes", without qualification, usually refers to diabetes mellitus.
Heart disease accounts for approximately 50% of all deaths among people with diabetes in industrialized countries. Risk factors for heart disease in people with diabetes include smoking, high blood pressure, high serum cholesterol and obesity. Diabetes negates the protection from heart disease which pre-menopausal women without diabetes experience. Recognition and management of these conditions may delay or prevent heart disease in people with diabetes.
Gestational diabetes mellitus (GDM) resembles type 2 DM in several respects, involving a combination of relatively inadequate insulin secretion and responsiveness. It occurs in about 2–10% of all pregnancies and may improve or disappear after delivery.[50] However, after pregnancy approximately 5–10% of women with GDM are found to have DM, most commonly type 2.[50] GDM is fully treatable, but requires careful medical supervision throughout the pregnancy. Management may include dietary changes, blood glucose monitoring, and in some cases, insulin may be required.

^ Jump up to: a b Petzold A, Solimena M, Knoch KP (October 2015). "Mechanisms of Beta Cell Dysfunction Associated With Viral Infection". Current Diabetes Reports (Review). 15 (10): 73. doi:10.1007/s11892-015-0654-x. PMC 4539350. PMID 26280364. So far, none of the hypotheses accounting for virus-induced beta cell autoimmunity has been supported by stringent evidence in humans, and the involvement of several mechanisms rather than just one is also plausible.

By simultaneously considering insulin secretion and insulin action in any given individual, it becomes possible to account for the natural history of diabetes in that person (e.g., remission in a patient with T1 diabetes or ketoacidosis in a person with T2DM). Thus, diabetes mellitus may be the result of absolute insulin deficiency, or of absolute insulin resistance, or a combination of milder defects in both insulin secretion and insulin action.1 Collectively, the syndromes of diabetes mellitus are the most common endocrine/metabolic disorders of childhood and adolescence. The application of molecular biologic tools continues to provide remarkable insights into the etiology, pathophysiology, and genetics of the various forms of diabetes mellitus that result from deficient secretion of insulin or its action at the cellular level.
Insulin, a hormone released from the pancreas (an organ behind the stomach that also produces digestive enzymes), controls the amount of glucose in the blood. Glucose in the bloodstream stimulates the pancreas to produce insulin. Insulin helps glucose to move from the blood into the cells. Once inside the cells, glucose is converted to energy, which is used immediately, or the glucose is stored as fat or glycogen until it is needed.

All children with type 1 diabetes mellitus require insulin therapy. Most require 2 or more injections of insulin daily, with doses adjusted on the basis of self-monitoring of blood glucose levels. Insulin replacement is accomplished by giving a basal insulin and a preprandial (premeal) insulin. The basal insulin is either long-acting (glargine or detemir) or intermediate-acting (NPH). The preprandial insulin is either rapid-acting (lispro, aspart, or glulisine) or short-acting (regular).
Diabetes mellitus is classified into four broad categories: type 1, type 2, gestational diabetes, and "other specific types".[11] The "other specific types" are a collection of a few dozen individual causes.[11] Diabetes is a more variable disease than once thought and people may have combinations of forms.[37] The term "diabetes", without qualification, usually refers to diabetes mellitus.
In type 2 diabetes (formerly called non– insulin-dependent diabetes or adult-onset diabetes), the pancreas often continues to produce insulin, sometimes even at higher-than-normal levels, especially early in the disease. However, the body develops resistance to the effects of insulin, so there is not enough insulin to meet the body’s needs. As type 2 diabetes progresses, the insulin-producing ability of the pancreas decreases.
Several tests are helpful in identifying DM. These include tests of fasting plasma glucose levels, casual (randomly assessed) glucose levels, or glycosylated hemoglobin levels. Diabetes is currently established if patients have classic diabetic symptoms and if on two occasions fasting glucose levels exceed 126 mg/dL (> 7 mmol/L), random glucose levels exceed 200 mg/dL (11.1 mmol/L), or a 2-hr oral glucose tolerance test is 200 mg/dL or more. A hemoglobin A1c test that is more than two standard deviations above normal (6.5% or greater) is also diagnostic of the disease.
Merck & Co., Inc., Kenilworth, NJ, USA is a global healthcare leader working to help the world be well. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world. The Merck Manual was first published in 1899 as a service to the community. The legacy of this great resource continues as the Merck Manual in the US and Canada and the MSD Manual outside of North America. Learn more about our commitment to Global Medical Knowledge.
From a dental perspective, pregnancy leads to hormonal changes that increase the mother’s risk of developing gingivitis and gingival lesions called pregnancy tumors (see Right). Not surprisingly, poor glycemic control further adds to this risk. Therefore, it is imperative that if you become pregnant, you should promptly see your dentist. He or she will work with you to ensure that your dental self-care regimen is maximized to prevent or control your dental disease. Additional Resources on Diabetes and Oral Health National Institute of Dental and Craniofacial Research www.nidcr.nih.gov American Diabetes Association www.diabetes.org American Dental Association www.dental.org American Academy of Periodontology www.perio.org The Diabetes Monitor www.diabetesmonitor.com David Mendosa www.mendosa.com Diatribe www.diatribe.us The information contained in this monograph is for educational purposes only. This information is not a substitute for professional medical advice, diagnosis, or treatment. If you have or suspect you may have a health concern, consult your professional health care provider. Reliance on any information provided in this monograph is solely at your own risk.

If you are symptomatic (e.g., increased thirst or urination, unexplained weight loss), your doctor may only use a single test to diagnose diabetes/prediabetes. If you don't have any symptoms, one high blood glucose test doesn't necessarily mean you have diabetes/prediabetes. Your doctor will repeat one of the blood tests again on another day (generally 1 week later) to confirm the diagnosis.

Classic symptoms of DM are polyuria, polydipsia, and weight loss. In addition, patients with hyperglycemia often have blurred vision, increased food consumption (polyphagia), and generalized weakness. When a patient with type 1 DM loses metabolic control (such as during infections or periods of noncompliance with therapy), symptoms of diabetic ketoacidosis occur. These may include nausea, vomiting, dizziness on arising, intoxication, delirium, coma, or death. Chronic complications of hyperglycemia include retinopathy and blindness, peripheral and autonomic neuropathies, glomerulosclerosis of the kidneys (with proteinuria, nephrotic syndrome, or end-stage renal failure), coronary and peripheral vascular disease, and reduced resistance to infections. Patients with DM often also sustain infected ulcerations of the feet, which may result in osteomyelitis and the need for amputation.

Insulin — the hormone that allows your body to regulate sugar in the blood — is made in your pancreas. Essentially, insulin resistance is a state in which the body’s cells do not use insulin efficiently. As a result, it takes more insulin than normal to transport blood sugar (glucose) into cells, to be used immediately for fuel or stored for later use. A drop in efficiency in getting glucose to cells creates a problem for cell function; glucose is normally the body’s quickest and most readily available source of energy.
With such a surplus of food nowadays, it's easy to overindulge without physical activity, leading to weight gain and, for some people, eventual Type 2 diabetes. "It's a lack of exercise and still eating like you're 20 years old," says Susan M. De Abate, a nurse and certified diabetes educator and team coordinator of the diabetes education program at Sentara Virginia Beach General Hospital.
At the same time that the body is trying to get rid of glucose from the blood, the cells are starving for glucose and sending signals to the body to eat more food, thus making patients extremely hungry. To provide energy for the starving cells, the body also tries to convert fats and proteins to glucose. The breakdown of fats and proteins for energy causes acid compounds called ketones to form in the blood. Ketones also will be excreted in the urine. As ketones build up in the blood, a condition called ketoacidosis can occur. This condition can be life threatening if left untreated, leading to coma and death.
Talk with your doctor about connecting with a certified diabetes educator and receiving diabetes self-management education. Learning about what to eat, what your medicines do, and how to test your blood sugars are just some of the things these resources can help with. Educators can also dispel myths, create meal plans, coordinate other doctors appointments for you, and listen to your needs. They are trained to teach using a patient-centered approach. They are your advocates who specialize in diabetes. Ask your doctor today or go to the American Association of Diabetes Educators website to find someone near you. Be sure to call your insurance company to see if these services are covered, too.
The protocol for therapy is determined by the type of diabetes; patients with either type 1 or type 2 must pay attention to their diet and exercise regimens. Insulin therapy may be prescribed for patients with type 2 diabetes as well as any who are dependent on insulin. In most cases, the type 2 diabetes patient can be treated effectively by reducing caloric intake, maintaining target weight, and promoting physical exercise.
Metformin is generally recommended as a first line treatment for type 2 diabetes, as there is good evidence that it decreases mortality.[6] It works by decreasing the liver's production of glucose.[87] Several other groups of drugs, mostly given by mouth, may also decrease blood sugar in type II DM. These include agents that increase insulin release, agents that decrease absorption of sugar from the intestines, and agents that make the body more sensitive to insulin.[87] When insulin is used in type 2 diabetes, a long-acting formulation is usually added initially, while continuing oral medications.[6] Doses of insulin are then increased to effect.[6][88]

Type 2 diabetes is a preventable disease that affects more than 9 percent of the U.S. population, or about 29 million people. According to the Centers for Disease Control and Prevention, more than a quarter — some 8 million people — remain undiagnosed. With complications including nerve damage, kidney damage, poor blood circulation, and even death, it’s important for us all to know the early signs of type 2 diabetes.